Workers in tall construction projects continually face the danger of falling great distances to the ground. Such workers often must walk along narrow beams and perform difficult and awkward tasks at very high elevations. This is particularly true in the case of skyscrapers and the like constructed of structural steel I-beams. Even where the height is not as great, e.g., twenty or thirty feet above the floor, a fall from that height onto a concrete surface can seriously injure a worker.
In order to protect the worker against the danger of falling, a device is needed to attach the worker to the structure while permitting freedom of movement sufficient to allow the worker to complete his tasks without interference from the attaching device. Furthermore, the worker needs to be able to move the attaching device from place to place easily. The device must therefore be readily connected to and disconnected from the structure. Prior attempts to provide safety devices for workers are shown in U.S. Pat. Nos. 2,303,954, 3,217,833 and 4,171,032. These devices are relatively complex, and do not combine inexpensive construction with the advantages of positive attachment to the structure and ease of movement of the device from place to place.
U.S. Pat. No. 1,128,277 discloses a prior art device for gripping and hoisting I-beams. U.S. Pat. No. 494,868 discloses a support for a ladder or scaffold.